Known lockable plug connector systems, including a plug connector and an axially connected plug counter-connector, are protected against unintentional disengagement by means of locking devices. The known plug connector generally comprises two housing portions, a connector body and a sliding sleeve which is arranged in an axially movable manner. When the plug system is assembled, the plug counter-connector and the plug connector are engaged by means of the sliding sleeve. When the plug system is disassembled, the sliding sleeve is displaced in an insertion direction away from the plug counter-connector in order to release the engagement of the plug system.
Generally, such known plug systems are electrical plug connections which are intended to be constructed in a correspondingly robust and durable manner. It has been found to be disadvantageous for the connector body and the sliding sleeve to be produced from a non-resilient material, for example, a metal. Furthermore, previously known plug connectors with catch connections are cost-intensive to produce.